Hydrothermally Synthesized ZnMn2O4@GO Cathode Enhances Zinc-Ion Kinetics and Cycling Stability for Aqueous Zinc-Ion Batteries

Spinel-type ZnMn2O4 has been identified as a cathode that demonstrates considerable potential material for zinc-ion batteries (ZIBs). In this study, the synthesis of ZnMn2O4@GO composite material was conducted using a hydrothermal method. The electrochemical performance of the composite material was found to be significantly enhanced, a phenomenon that was primarily ascribed to the substantial specific surface area and exceptional conductivity of graphene, which improved the diffusion kinetics of zinc ions at the electrode-electrolyte interface. At a current density of 50 mA g(-1), the discharge capacity of the ZnMn2O4@GO composite electrode was 186.4 mAh g(-1), much higher than that of ZnMn2O4 (133.3 mAh g(-1)). Moreover, after 1000 charge-discharge cycles at a current density of 1000 mA g(-1), the discharge capacity of ZnMn2O4@GO composite electrode was 50% higher than that of ZnMn2O4.